Beam management for multi-TRP

Abstract

Methods and apparatus for beam management are disclosed. A WTRU may include a plurality of antenna panels, each antenna panel comprising a plurality of antennas configured to transmit on directional transmit (TX) beams. The WTRU may send, to a transmission reception point (TRP), antenna panel capability information for the plurality of antenna panels and receive a reference signal (RS) configuration for configuring RS resource sets. The WTRU may send an RS transmission trigger frame identifying triggered RS resource sets from the configured RS resource sets. The WTRU may identify a set of antenna panels to be used with the triggered RS resource sets. The WTRU may determine an UL TX beam sweeping mode and an association between the triggered RS resources sets and the set of antenna panels. The WTRU may perform UL beam sweeping using the triggered RS resource sets and associated set of antenna panels.

What is claimed is: 
     
       1. A multi-panel wireless transmit and/or receive unit (WTRU) comprising:
 a transceiver; 
 a processor; and 
 a plurality of antenna panels, each antenna panel comprising a respective plurality of antennas, wherein 
 the transceiver, the processor and the plurality of antenna panels are configured to: 
 send, to a transmission reception point (TRP), antenna panel capability information for the plurality of antenna panels; 
 receive, from the TRP, a reference signal (RS) configuration for configuring RS resource sets, wherein the RS configuration includes time and frequency location information of the configured RS resource sets; 
 receive, from the TRP, a first message including an indication of RS resource sets from the configured RS resource sets and an indication of antenna panel identities (IDs) or beam IDs associated with the plurality of antenna panels; and 
 send, using a set of antenna panels from the plurality of antenna panels, reference signals using the indicated RS resource sets, wherein the set of antenna panels is determined based on the received RS configuration and the received first message. 
 
     
     
       2. The WTRU of  claim 1 , wherein the plurality of antenna panels are homogeneous with similar transmit beam capabilities or heterogeneous with different transmit beam capabilities. 
     
     
       3. The WTRU of  claim 2 , wherein the transmit beam capabilities include at least one of the following: a number of supported beams or a magnitude of directional coverage. 
     
     
       4. The WTRU of  claim 1 , wherein the antenna panel capability information for the plurality of antenna panels includes at least one of the following: a number of WTRU antenna panels; antenna panel identifiers (IDs); or a number of supported beams for each antenna panel. 
     
     
       5. The WTRU of  claim 1 , wherein the RS configuration further indicates antenna panel IDs or directional beam IDs associated with the configured RS resource sets. 
     
     
       6. The WTRU of  claim 1 , wherein the indicated antenna panel IDs or beam IDs override previously signaled antenna panel IDs or beam IDS associated with the plurality of antenna panels. 
     
     
       7. The WTRU of  claim 1 , wherein the transceiver, the processor, and the plurality of antenna panels are further configured to:
 receive, from the TRP, a second message including an indication of RS resources for multi-panel uplink (UL) physical uplink shared channel (PUSCH) transmission using multiple antenna panels from the plurality of antenna panels. 
 
     
     
       8. The WTRU of  claim 1 , wherein the RS is a sounding reference signal (SRS). 
     
     
       9. The WTRU of  claim 1 , wherein the transceiver, the processor, and the plurality of antenna panels are further configured to:
 determine an uplink transmission beam sweeping mode based on the at least one of the RS configuration of the first message, wherein the determined uplink transmission beam sweeping mode is one of a sequential uplink transmission beam sweeping mode and a simultaneous uplink transmission beam sweeping mode. 
 
     
     
       10. A method, performed by a multi-panel wireless transmit and/or receive unit (WTRU) comprising a plurality of antenna panels, the method comprising:
 sending, to a transmission reception point (TRP), antenna panel capability information for the plurality of antenna panels; 
 receiving, from the TRP, a reference signal (RS) configuration for configuring RS resource sets, wherein the RS configuration includes time and frequency location information of the configured RS resource sets; 
 receiving, from the TRP, a first message including an indication of RS resource sets from the configured RS resource sets and an indication of antenna panel identities (IDs) or beam IDs associated with the plurality of antenna panels; and 
 sending, using a set of antenna panels from the plurality of antenna panels, reference signals using the indicated RS resource sets, wherein the set of antenna panels is determined based on the received RS configuration and the received first message. 
 
     
     
       11. The method of  claim 10 , wherein the plurality of antenna panels are homogeneous with similar transmit beam capabilities or heterogeneous with different transmit beam capabilities. 
     
     
       12. The method of  claim 10 , wherein the antenna panel capability information for the plurality of antenna panels includes at least one of the following: a number of WTRU antenna panels; antenna panel identifiers (IDs); or a number of supported beams for each antenna panel. 
     
     
       13. The method of  claim 10 , wherein the RS configuration further indicates antenna panel IDs or directional beam IDs associated with the configured RS resource sets. 
     
     
       14. The method of  claim 10 , wherein indicated antenna panel IDs or beam IDs override previously signaled antenna panel IDs or beam IDS associated with the plurality of antenna panels. 
     
     
       15. The method of  claim 10 , further comprising:
 receiving, from the TRP, a second message including an indication of RS resources for multi-panel uplink (UL) physical uplink shared channel (PUSCH) transmission using multiple antenna panels from the plurality of antenna panels. 
 
     
     
       16. The method of  claim 10 , wherein the RS is a sounding reference signal (SRS). 
     
     
       17. The method of  claim 10 , further comprising:
 determining an uplink transmission beam sweeping mode based on at least one of the RS configuration or the first message, wherein the determined uplink transmission beam sweeping mode is one of a sequential uplink transmission beam sweeping mode and a simultaneous uplink transmission beam sweeping mode.